1. Field of the Invention
This invention relates to a sight apparatus to be used with firearms, archery bows and other weapons or hunting instruments. It is more particularly concerned with a sight apparatus that centers a target using the natural characteristics of the human eye, and the sight apparatus is adaptable to a variety of instruments.
2. Discussion of the Prior Art
Non-optical sight devices are popular because they are inexpensive and easy to use. However, prior non-optical sight devices used with weapons and hunting devices display several limitations overcome by the present invention and place the human eye at a disadvantage.
Sight devices comprising rear and front alignment members such as a rear notched member and front post sights are very common, but these devices force the human eye to focus and align to the post, which represents a very close object. While the human eye is focused on a very close object, the intended target is typically distant. The focus on the close object negatively effects the ability of the human to properly focus and align on a distant target.
Attempts have been made to improve sight devices similar to the notched rear sight member with front sight post design. For instance, luminescent materials have been provided on the post or device for use in darkened conditions as in U.S. Pat. No. 3,641,676 to Knutsen and Santiago. These luminescent materials aid in rear sight and front sight alignment, but still force the human eye to focus and align two objects that are closer to the human eye than the target. More recent designs that suggest using luminescent outlines and dots in gun sights to align a target also force the human eye to focus on the closer image of the sight device rather than the target. Thus, professional handgun shooters usually have a clear picture of the sight device or the target, but not both.
Still other examples exist of similar sight devices with these drawbacks. For example, U.S. Pat. No. 3,777,380 to Paris Theodore employs a rear v-shaped notch connected by a block with a channel groove used for alignment with a target, and U.S. Pat. No. 4,918,823 to Julio A. Santiago adds a post to a similar channel sight device. These type of non-optical sights continue to depend on the human eye lining up closer objects and demand the eye to focus on those closer objects to center a distant object, causing the distant target to remain out of focus. The problem is further exacerbated when a person is nearsighted or farsighted causing the person to readily misalign a sight picture. Sights having a front sight ring and a rear sight ring are well-known, but very similar to sights having front and rear alignment members. U.S. Pat. No. 3,744,143 to David D. Kilpatrick describes a front sight ring and rear sight ring that when perfectly aligned by the shooter""s eye provides a clear sight picture. The rings in the ""143 patent are not connected without longitudinal alignment by the shooter""s eye, and, therefore, the human eye has to align the closer ring objects to focus a clear sight picture, similar to front and rear alignment member schemes discussed above. Such sight rings are disadvantageous also because they are subject to snagging. U.S. Pat. No. 4,215,495 to Donald G. Wagner connects two holes in sheet metal arms in a fixed assembly, which still requires alignment of two closer sight objects by the eye, rather than allowing the eye to focus on the distant target.
Another variety of non-optical sight devices that are well-known in the prior art are tubular sights and modifications thereto that provide a tunneling effect for aligning a target. For example, U.S. Pat. No. 4,048,726 to Albert W. LeFebure shows a sight tube for a bow, and U.S. Pat. No. 5,471,777 to Kenneth E. McDonald shows a sight tube for a firearm towards the muzzle end of the firearm to reduce dominant-eye misalignment. While a tube may reduce dominant eye misalignment, a tubular sight generally causes a tunneling effect that requires maintenance of constant and equal shadow as the tube gets longer causing a common misalignment problem. The tube""s diameter or radius from the center appears to get smaller because the human eye naturally narrows the aperture at the distal end of the tube, making sighting and alignment of a target more difficult. Enhancement such as lights, dots, posts and other alignment members have been proposed but only confuse the sight picture even further.
Optical devices and light projecting sights provide a solution to some of the problems discussed. However, optical devices such as lenses, mirrors, and telescopic devices which aid the human eye are generally more expensive and limited to use in certain environmental conditions. Light projecting sights such as lasers allow the use of the full function of the human eyes but like optical devices are expensive and may not be used under all light conditions. Further, such optical devices and light projecting sights are often bulky and encumber the sleek profile of a gun or bow.
As discussed, prior art sighting mechanisms are either very expensive or compromise the natural abilities of the human eye, leading to a less desirable sighting device. Therefore, a need exists for an sighting apparatus that is inexpensive to manufacture. In particular a non-optical sighting apparatus is needed that does not require the alignment of closer sight members or objects closer than the target or provide a tunneling effect.
The inventor has found that the optimal sighting apparatus should utilize the natural abilities of the human eye to align a target in the center of a unitized longitudinal circular sight. In order to have an accurate sighting device, the user""s eye must see a perfectly aligned sight picture automatically and should focus on the target. The human eye should not be forced to focus on objects that are closer than the target. Further, the sight picture should not be encumbered by any objects such as post members.
A desirable sighting device should be unobtrusive, cheap to manufacture, and adjustable. The sighting device should enhance profile of weapon and should not be prone to snag. Further, the sighting device should be adaptable to a variety of weapons including firearms and archery bows, and should be adaptable to integrate with or supplement a weapon or hunting device.
The present invention allows a user""s eye to perfectly align a sight picture automatically. The sight apparatus of the invention relies on the natural ability of the human eye to center an object in a field of vision as seen through a circle, while allowing the eye to focus on the target without obstruction. The sight apparatus provides a non-optical sight device that is inexpensive to manufacture and highly adaptable to supplement or incorporate into a variety of weapons and hunting instruments, such as pistols, rifles, and archery bows. Further, the sight apparatus taught herein is unobtrusive when adapted to a surface and is not prone to snag is deface the profile of the instrument.
The sighting apparatus includes a mounting assembly having a base for securing the sight apparatus to a surface such as on a gun or bow. A retaining member on the mounting assembly is removable or may be opened to accommodate a replaceable internal sight mechanism that is set within the base. Enhancements to the mounting assembly may be made to optimize light, such as a pattern of apertures or provision of light collecting material.
The internal sight mechanism includes a central portion with an enlarged girth for securing the sight mechanism with respect to the base and the retaining member. In the preferred embodiment the central portion has an elliptical shape. The elliptical shape of the central portion provides for the sight mechanism to have a proximal end and a distal end separated by the central portion, and the proximal end and the distal end each have an external girth that is reduced with respect to the enlarged girth of the central portion.
The enlarged girth of the central portion assists in securing the internal sight mechanism to the mounting assembly, and slip resistant material may be added to the central portion to assist in securing the sight mechanism. Set screws through the mounting assembly contact the central portion to affix the sight mechanism in position.
The reduced girth of the proximal and distal ends provide excellent location points for windage and elevation adjusting devices to contact the internal sight mechanism and operate for adjusting the sighting apparatus. Such windage and elevation adjustment devices are set in the mounting assembly in operable relation to the sight mechanism.
The sight mechanism includes a circular aperture that passes through the proximal end, the central portion, and the distal end. A proximal circular member providing a perfect circle for the human eye to view the target through is attached to the proximal end of the sight mechanism. The proximal circle member has an aperture that is perfectly aligned in contiguous relation to the circular aperture of the sight mechanism. A distal circular member providing a perfect circle is attached to the distal end of the sight mechanism and has an aperture that is perfectly aligned in contiguous relation to the circular aperture of the sight mechanism. The proximal circular member and distal circular member are removable.
When the circumstances cause the configuration of the circular members and internal sight mechanism to present a tunneling effect, the circular members may be easily removed from the internal sight mechanism and replaced with circular members that are shorter longer. Thus, the sight apparatus may be adapted without effecting the adjustment of the windage and elevation or the alignment of the sight. Alternatively, the internal sight mechanism may be completely removed and replaced with one that is shorter or longer or provides a different aperture size.
In operation the longitudinal aperture through the internal sight mechanism combined with the circular member are not long enough for human eye to narrow sides of distal end and cause a tunneling effect. Therefore, any view or shadow of the sides of the proximal circle member destroys the perfect circle and indicates misalignment with the target. Likewise, if any edges the of distal circle member become prominent in the sight picture, the sight picture is misaligned.